1. Field of the Invention
The present invention relates to a method of checking the post-erasure contents of an erasable permanent memory, especially of EPROM type.
It also concerns a device for its implementation as well as a memory incorporating this device.
2. Discussion of the Related Art
Rational use of erasable permanent memories, especially of EPROM type, involves systematic checking of the contents of these memories after every erasure operation.
Now, hitherto, the checking of the contents of a memory after erasure was performed by writing an instruction into an instruction register of the memory, having the effect of storing the value of an address and of reading the contents at this address after a necessary recovery time which, by way of example, may be of the order of 6 .mu.s.
This operation of writing an instruction and of reading must be performed for each address to be checked, this entailing significant loss of time in an industrial context. Furthermore, such checking is performed several times while the memory has not been acknowledged to be completely erased, which may lead to a total checking time greater than a second.